Quaternary ammonium hydroxide compositions and preparation thereof

ABSTRACT

A high yield method for the preparation of C 1  -C 20  alkyl or aryl-substituted alkyl, C 8  -C 16  alkyl quaternary ammonium-hydroxide is provided whereby two reactants, a corresponding quaternary ammonium chloride and a metal hydroxide, are reacted in a solvent comprising a C 1  -C 4  normal alcohol. The amount of metal hydroxide reactant is that amount sufficient to yield the quaternary ammonium hydroxide and a metal chloride. 
     Also provided are wood preservative systems which include (a) a biocidal effective amount of at least one di C 8  -C 12  alkyl quaternary ammonium hydroxide and (b) a solvent, as well as a method for preserving a wood substrate whereby the substrate is treated with the preservative system.

    __________________________________________________________________________    Table of Related Applications                                                 Attorney's                                                                    Docket No.                                                                          Appln. No.                                                                          Dated Filed                                                                          Title           Inventor                                   __________________________________________________________________________    5408/07432                                                                          08/074,312                                                                          9 June 1993                                                                          Quaternary Ammonium                                                                           Leigh E. Walker                                               Carbonate Compositions                                                        and Preparation Thereof                                    5408/07424                                                                          08/074,136                                                                          9 June 1993                                                                          Quaternary Ammonium                                                                           Leigh E. Walker                                               Carboxylate Compositions                                                      and Preparation Thereof                                    5408/07426                                                                          08/074,314                                                                          9 June 1993                                                                          Waterproofing and Preservative                                                                Leigh E. Walker                                               Compositions and Preparation                                                  Thereof                                                    __________________________________________________________________________

FIELD OF THE INVENTION

This invention relates to the preparation of C₁ -C₂₀ alkyl oraryl-substituted alkyl, C₈ -C₂₀ alkyl quaternary ammonium hydroxidecompositions by an indirect synthesis method which uses a correspondingquaternary ammonium chloride as a starting material. Di C₈ -C₁₂ alkylquaternary ammonium compositions, preferably prepared according to themethod of the present invention, are useful in wood preservativesystems, as surfactants, and as biocides. Preferably, these woodpreservative systems are metal free.

BACKGROUND OF THE INVENTION

Quaternary ammonium compounds (quats) are typically prepared by thereaction:

    R.sup.1 R.sup.2 R.sup.3 N+R.sup.4 X→R.sup.1 R.sup.2 R.sup.3 R.sup.4 NX                                                        (I)

wherein X is a halogen, a sulfate, a sulfo compound, or the like. Whenat least one of R¹, R², R³, or R⁴ is C₁₂ or longer, the product is aninert soap. Many of the inert soaps have biocidal activity againstbacteria, fungi, algae, and related organisms.

Reaction (I) above is limited by the reactant R⁴ X because R⁴ must reactwith tertiary amines. For example, methyl chloride (R⁴ X═CH₃ Cl) willreact with a tertiary amine at less than 100° C. to yield a quaternarycompound R₃ N⁺ CH₃ Cl⁻, while methanol or methyl acetate (R⁴ X═CH₃ OH orCH₃ COOCH₃) will not, under similar reaction conditions.

General quaternary ammonium compounds with a sulfo group are easilyprepared either by the reaction of a sulfate compound with a tertiaryamine (II) or by a double exchange (III).

    R.sub.3 N+RSO.sub.3 CH.sub.3 →R.sub.3 NCH.sub.3.sup.+ RSO.sub.3.sup.-(II)

    R.sub.3 N.sup.+ CH.sub.3 Cl.sup.- +RSO.sub.3.sup.-  Na.sup.+ →R.sub.3 NCH.sub.3.sup.+ RSO.sub.3.sup.- +NaCl     (III)

Quaternary ammonium hydroxides (hydroxy quats) are currently prepared bythe reaction of quaternary ammonium iodide with silver oxide (IV).

    RN.sup.+ (CH.sub.3).sub.3 I.sup.- +AgO→RN.sup.+ (CH.sub.3).sub.30 H.sup.- +AgI                                              (IV)

However, this reaction is costly, and it is difficult to recover thesilver reagent. See, Organic Reactions, 11:Chptr 5, pp. 376-377, KriegerPublishing Co., 1975.

In an olefin synthesis, it has been suggested to treat a quaternary saltwith aqueous sodium or potassium hydroxide followed by pyrolysis inorder to form the hydroxy quat and then to decompose the hydroxy quatdirectly. However, in this method the hydroxy quat is not isolated andthe conditions for its preparation are undesirable. See, OrganicReactions, 11:Chptr 5, pp. 376-377, Krieger Publishing Co., 1975.

Talmon et al., Science, 221, 1047 (1983), have used an ion exchangeresin to convert didecyldimethylammonium bromide todidecyldimethylammonium hydroxide (V).

    (C.sub.12 H.sub.25).sub.2 (CH.sub.3)N.sup.+ Br.sup.- +Ion Exchange Resin→(CH.sub.12 H.sub.25).sub.2 (CH.sub.3).sub.2 N+OH.sup.-(V)

However, 50 ml of ion exchange resin and two treatment steps wererequired to convert 3 grams of quaternary ammonium chloride to thecorresponding hydroxide. See also, Organic Synthesis, Collective VolumeVI, 552, John Wiley Inc., 1988; Brady et al. J. Am. Chem. Soc.,106:4280-4282, 1984; Brady et al. J. Phys. Chem., 90:9, 1853-1859, 1986;Miller et al. J. Phys. Chem, 91:1, 323-325, 1989; Radlinske et al.Colloids and Surfaces, 46:213-230, 1990.

Alternatively, quaternary ammonium hydroxide compositions have beenprepared by treating a haloquat in an electrochemical cell with specialcation exchange diaphragms between the cells. The hydroxy quat collectsat one electrode, and the halide collects at the other. See, JapanesePatent Publication No. 02-106,915; Awata et al., Chemistry, Letters, 371(1985).

Japanese Patent Publication No. 01-172,363 discloses the preparation ofrelatively low yields of tetraethylammonium hydroxide by reactingtriethylamine with diethyl sulfate, heating the resultant quat withsulfuric acid to yield the sulfate quat, and reacting the sulfate quatwith barium hydroxide to yield the short chain quat, tetraethylammoniumhydroxide, and barium sulfate.

Di C₈ -C₁₂ alkyl quaternary ammonium hydroxides prepared by ion exchangewere used as strong bases to digest animal tissue by Bush et al., FrenchPatent Publication No. 1,518,427.

Akzo discloses that the addition of a metallic hydroxide to a quaternaryammonium chloride such as didecyldimethylammonium chloride, in anaqueous medium, results in an equilibrium mixture of quaternary ammoniumchloride and quaternary ammonium hydroxide (VI). This reaction can bedriven to the right by the use of isopropanol as a solvent.

    (R.sub.4 N)Cl+KOH (R.sub.4 N)OH+KCl                        (VI)

Quaternary ammonium compounds (quats) and particularlydidecyldimethylammonium chloride (DDAC) ##STR1## could be used as woodpreservatives if they were stable because they possess resistanceproperties to fungi and termites, to loss of strength, and to electricalsensitivity similar to those of commonly used acidiccopper/chromium/arsenic solution (CCA) or ammoniacal copper and arsenicsalt solution preservatives. See Proc of the Am. Wood Pres. ASSOC.,80:191-210 (1984). Although chloride quats do not include potentiallydangerous heavy metals, didecyldimethylammonium chloride leaches rapidlyin soil (Nicholas et al., Forest Prod. J., 41:41 (1991), and therefore,does require coupling with copper salt.

Findlay et al., U.S. Pat. No. 4,929,454, disclose a method of preservingwood by impregnation with a quaternary ammonium compound and at leastone of zinc and copper, wherein the quat anion is chosen from the groupconsisting of hydroxide, chloride, bromide, nitrate, bisulfate, acetate,bicarbonate, and carbonate, formate, borate and fatty acids. These quatshave distinct environmental and safety advantages over commonly usedacidic copper/chromium/arsenic solution (CCA) or ammoniacal copper andarsenic salt solution preservatives in that potentially dangerous heavymetals are not included. The Findlay et al. quats require copper or zincin order to render them relatively insoluble and to prevent them fromleaching out of a treated substrate. The use of copper or zinc in theabove formulations may yet raise environmental and corrosion concerns.

Additionally, didecyldimethylammonium chloride tends to absorbpreferentially to the surface of the wood and does not uniformly treatthe whole substrate. Finally, DDAC treated wood shows surface erosion orages upon exposure to light. See Preston et al., Proc. Am. Wood Pres.Assoc., 83:331 (1987).

The biocidal activities of various chloride quats against bacteria,fungi, and algae are tabulated in Cationic Surfactants, E. JungermanEd., pp. 56-57, Marcel Dekker, Inc., 1969. Nicholas, "Interaction ofPreservatives with Wood", Chemistry of Solid Wood, Advance in ChemistrySeries #207, Powell ed., (A.C.S. 1984) notes thatdidecyldimethylammonium compounds and particularly DDAC are potentialbiocides. Preston, J.A.O.C.S. 60:567 (1983) concurs and suggests thatmaximum fungitoxicity is exhibited with dialkyldimethyl compounds havingC₁₀ -C₁₂ alkyl groups. Butcher et al., Chem Abstracts No. 91:152627b,suggests that the presence of an acid or a base can affect the activityof didecyldimethylammonium quats.

Consequently, efforts have been directed to develop a safe, efficientand expedient method to prepare quaternary ammonium compounds that donot require potentially hazardous metal additives to treat woodensubstrates effectively.

DESCRIPTION OF THE DRAWINGS

FIG. 1A is a graphic comparison of leaching of a wood preservativesystem according to the present invention and a wood preservative systemof the prior art.

FIG. 1B is an enlarged segment of the graph of FIG. 1A.

SUMMARY OF THE INVENTION

A high yield method for the preparation of C₁ -C₂₀ alkyl oraryl-substituted alkyl, C₈ -C₂₀ alkyl quaternary ammonium hydroxide, andpreferably di C₈ -C₁₂ alkyl quaternary ammonium hydroxide, whichincludes the selection of particular solvents, has been discovered.Product yield can be further enhanced by adjustment of the amounts ofthe reactants. These hydroxy quats and wood preservative compositionsprepared therefrom can be applied to wood substrates with relativelyinsignificant leaching from the substrate.

The method of the present invention comprises reacting two reactants, aC₁ -C₂₀ alkyl or aryl-substituted alkyl, C₈ -C₂₀ alkyl quaternaryammonium chloride, preferably a di C₈ -C₁₂ alkyl quaternary ammoniumchloride, and a metal hydroxide, in a solvent comprising a C₁ -C₄ normalalcohol. The amount of metal hydroxide reactant is that amountsufficient to yield the C₁ -C₂₀ alkyl or aryl-substituted alkyl, C₈ -C₂₀alkyl quaternary ammonium hydroxide and a metal chloride. Preferably,this amount is at least a stoichiometric amount.

Also contemplated by the invention are wood preservative systems thatpreferably are metal-free and which include a biocidal effective amountof at least one di C₈ -C₁₂ alkyl ammonium hydroxide and a solvent.Preferably, the di C₈ -C₁₂ alkyl quaternary ammonium hydroxide isprepared by the method above.

Further contemplated by the invention is a method for preserving a woodsubstrate. Accordingly, the substrate is treated with a these woodpreservative systems.

DETAILED DESCRIPTION OF THE INVENTION

The method of the present invention provides increased yields of C₁ -C₂₀alkyl or aryl-substituted alkyl, C₈ -C₂₀ alkyl quaternary ammoniumhydroxide, and preferably di C₈ -C₁₂ alkyl quaternary ammoniumhydroxide, when compared with conventional production methods. Althoughit was previously believed that the reaction of the chloride quat saltwith a metal hydroxide to yield quaternary ammonium hydroxide and metalchloride was an equilibrium reaction (VII) or could be driven to theright by the use of branched solvents, it has now been discovered thatby selection of the proper reactants, reaction medium, and/or reactionconditions (including reactant amounts), the reaction can be driven wellpast equilibrium to yield unprecedented greater amounts of C₁ -C₂₀ alkylor aryl-substituted alkyl, C₈ -C₂₀ alkyl quaternary ammonium hydroxide.

Although the present method can be used to prepare a variety of C₁ -C₂₀alkyl or aryl-substituted alkyl, C₈ -C₂₀ alkyl quaternary ammoniumhydroxide compounds, the preferred reaction product quat is a di C₈ -C₁₂alkyl quaternary ammonium hydroxide compound. Most preferred hydroxyquats are di n-C₈ -C₁₂ alkyl quaternary ammonium hydroxide,didecyldimethylammonium hydroxide, and di-n-decyldimethylammoniumhydroxide.

Didecyldimethylammonium hydroxide, when observed in a 70 to 80 percentby weight solution in a 50 percent by weight alcohol/50 percent byweight water solvent, is a yellow/orange liquid. This formulation has aflash point of about 134° F., and it is a highly alkaline material thatreacts with the phenolic OH of lignin.

The reaction is illustrated below. ##STR2## wherein R¹ is a C₁ -C₂₀alkyl or aryl-substituted alkyl group; R² is a C₈ -C₂₀ alkyl group; R³is a straight chain C₁ -C₄ alkyl group; M is a mono-, di-, or trivalentmetal; and m is one if M is monovalent, two if M is divalent, and threeif M is trivalent. Preferably R¹ is the same as R², i.e. a C₈ -C₁₂ alkylgroup.

Many C₁ -C₂₀ alkyl or aryl-substituted alkyl, C₈ -C₂₀ alkyl quaternaryammonium chlorides are suitable reactants, but di C₈ -C₁₂ alkylquaternary ammonium chloride is preferred, and didecyldimethylammoniumchloride, and particularly, di-n-decyldimethylammonium chloride are mostpreferred. The selections of the R¹ and R² substituents of the chloridequat reactant are determinative of the hydroxy quat product.

Special mention is also made of processes wherein R¹ is a methyl, butyl,C₈ alkyl, C₉ isoalkyl, C₁₀ alkyl, C₁₂ alkyl, C₁₄ alkyl or benzyl group;and R² is a C₁₀ alkyl, C₁₂ alkyl, C₁₄ alkyl or C₁₆ alkyl group.

The metal hydroxide reactant is a mono-, bi-, or trivalent metal,preferably a monovalent metal hydroxide, and most preferably an alkalimetal hydroxide such as sodium hydroxide or potassium hydroxide. Specialmention is made of potassium hydroxide. The metal chloride reactionproduct will precipitate and is easily removed, i.e. by filtration orthe like, yielding a hydroxy quat/solvent reaction product. The hydroxyquat can be separated therefrom by drying or the like.

The reaction is conducted in a solvent which comprises a C₁ -C₄ normalalcohol. Preferably, the solvent is ethanol, and most preferably,anhydrous ethanol.

The amount of metal hydroxide reactant typically is a stoichiometricamount with respect to the quaternary ammonium chloride reactant.Therefore, on a theoretical basis and if the reaction were complete andunequilibrated, there would be no excess of metal hydroxide reactantupon completion of the reaction. In practice, yield when using astoichiometric amount of metal hydroxide reactant will range from about65% to about 95%, but will vary, dependent in part upon the particularmetal hydroxide reactant.

Yield can be further improved over conventional methods by utilizationof a stoichiometric excess of metal hydroxide ranging from about 2% toabout 20% excess. If an excess of metal hydroxide is used, yield will beincreased to from about 95% to about 99%, again varying as above.

The unreacted metal hydroxide is soluble in the hydroxy quat/solventmixture. Any excess or unreacted metal hydroxide should be removed afterthe reaction is completed, and is preferably precipitated by subsequentreaction with carbon dioxide to yield the corresponding metal carbonate.The carbonate is insoluble in the hydroxy quat/solvent mixture and iseasily removed, i.e. by filtration or the like. Alternatively, a solidmetal bicarbonate, in which the metal corresponds to the metal of themetal hydroxide, can be added and slurried with the hydroxy quat/solventmixture. The soluble metal hydroxide reacts with solid bicarbonate toyield the insoluble metal carbonate. The metal carbonate does not reactfurther with the hydroxy quat.

Mixing, adding, and reacting of the components in the method of thepresent invention can be accomplished by conventional means known tothose of ordinary skill in the art. The order of addition of reactantsor solvent does not affect the process. Reactants and/or solvent can beadded sequentially or simultaneously in any suitable reaction vessel.For example, the metal hydroxide may be dissolved in alcohol and theresultant mixture added to the chloride quat or the chloride quat may bedissolved in alcohol and the metal hydroxide added to the resultantmixture. Importantly, the method of the present invention is suitablefor commercial scale production techniques and equipment, yet convenientfor small scale work.

Typically, the reactants and solvent will be stirred and heated to fromabout 20° C. to about 70° C. and held at that temperature for a periodof from about 1 hours to about 5 hours. The reaction mixture is thencooled, first to room temperature and then to about 0° C. where it isheld for about 1 hours to about 2 hours. Any precipitated metal chlorideis collected as is known in the art, i.e. such as by filtration.

Alternatively, the reactants and solvent can be stirred at a slightlyelevated temperature, i.e. from about 20° C. to about 40° C., to yieldthe hydroxy quat/solvent mixture. Hydroxy quat can be separated asabove.

Di C₈ -C₁₂ alkyl quaternary ammonium hydroxides, and particularly thoseprepared by the method of the present invention, can be formulated asmetal-free wood preservative systems. These systems include biocidaleffective amounts of at least one hydroxy quat and a suitable solvent,including aqueous and non-aqueous solvents. Preferably, the solvent isan aqueous solvent including, but not limited to, water, aqueous alcoholsuch as ethanol, ammonia water, and the like, or a combination of any ofthe foregoing.

Although other conventional additives may be added as required forapplication to different substrates and for different uses as known tothose of ordinary skill in the art, metal stabilizers are not requiredand, in fact, are not recommended to inhibit leaching of the quat fromthe substrate. Accordingly, wood substrates, such as lumber, timber, orthe like, can be treated with preservative systems which comprise theabove hydroxy quat(s) diluted in a suitable solvent as above.

The amount of di C₈ -C₁₂ alkyl quaternary ammonium hydroxide used totreat the substrate is a biocidal effective amount, i.e. that amounteffective to inhibit the growth of or to kill one or more organism thatcauses wood rot, to inhibit sap staining, or any combination thereof.Such organisms include, but are not limited to, Trametes viride orTrametes versicolor, which cause a white rot; Goeophyllium trabeum,which causes a brown rot; and Aspergillus niger, which causes sapstain/mold.

Typically, a wood preservative system will comprise from about 0.1 toabout 5 parts by weight of the hydroxy quat and from about 95 to about99.9 parts by weight of solvent based upon 100 parts by weight of quatand solvent combined. Most preferably, the wood preservative system ofthe present invention will comprise from about 1 to about 2 parts byweight of hydroxy quat and from about 98 to about 99 parts by weight ofsolvent on the same basis.

Treatment of the substrate is accomplished by any means known to thoseof ordinary skill in the art including, but not limited to dipping,soaking, brushing, pressure treating or the like. The length oftreatment required will vary according to treatment conditions, theselection of which are known to those skilled in the art.

The wood preservative systems of the present invention display greaterresistance to leaching than wood preservatives currently used in theindustry. Resistance to leaching is defined as retention of a biocidaleffective amount, and preferably at least about 2% by weight, of hydroxyquat in the substrate over a prolonged period of at least about 100hours and preferably about 350 hours. Applicants hypothesize, withoutbeing bound by any theory, that the hydroxide quat reacts or complexeswith the woody matrix of the substrate, thereby "fixing" it in thesubstrate. It is also believed that the long chain hydroxy quats and thewood preservative systems that include such quats enhance waterproofingproperties of the treated substrates.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following examples illustrate the invention without limitation. Allparts and percentages are given by weight unless otherwise indicated.

Quaternary compounds are quantified by two phase titration with sodiumlaurylsulfate and an indicator. The mixture is buffered to a pH of 10.

PREPARATION OF HYDROXY QUATS EXAMPLE 1 --STOICHIOMETRIC AMOUNT OF METALHYDROXIDE

180 grams (0.4 moles) of 80% didecyldimethylammonium chloride in 20%ethanol water (144 grams of DDAC), 180 ml of absolute denatured ethanol(denatured with methanol/isopropanol), and 26 grams (0.4 mole) of 85%potassium hydroxide pellets (22.1 grams of KOH) were mixed in a flaskthat was purged with nitrogen and equipped with a heating mantle and amagnetic stirrer. The mixture was stirred and heated at 60°-70° C. forthree hours. The mixture was then allowed to cool to room temperatureand finally cooled to 0° C. for at least one hour.

Potassium chloride precipitated, and the precipitate was collected on avacuum filter. The solid was washed with cold ethanol and subsequentlywas dried, yielding 30 grams of dry potassium chloride. The quatsolution was concentrated in a vacuum to about 75% active bases.

Yield was 180 grams of product containing 138 grams ofdidecyldimethylammonium hydroxide.

EXAMPLE 2

The procedure of Example 1 was followed, but the mixture was stirredmechanically at 50° C. for one hour. Potassium chloride precipitated,and the precipitate was-collected on a vacuum filter. The solid waswashed with cold ethanol and subsequently was dried, yielding 30 gramsof dry potassium chloride.

Yield was 180 grams of product containing 138 grams ofdidecyldimethylammonium hydroxide.

EXAMPLE 3

0.022 mole of 8.5% potassium hydroxide pellets (1.23 grams of KOH) wasadded to 0.022 mole of 80% didecyldimethylammonium chloride in 20%ethanol/water (8 grams of DDAC) dissolved in 10 ml of ethanol. Theresultant mixture was stirred and heated to 70° C. and held at thistemperature for one-half hour. The pellets dissolved, and a fineprecipitate formed. The mixture was then cooled and chilled to 0° C. Theprecipitated solid was collected on a filter and washed with coldethanol. The filtrate was concentrated to yield a yellow/orange oil witha slight amine odor.

Results are summarized in Table 1.

COMPARATIVE EXAMPLE 3A

The procedure of Example 3 was followed substituting isopropanol for theethanol.

Results are illustrated in Table 1.

EXAMPLE 4

0.022 mole of 85% potassium hydroxide pellets (1.23 grams of KOH) wasadded to 0.022 mole of 80% didecyldimethylammonium chloride in 20%ethanol/water (8 grams of DDAC) dissolved in 10 ml of propanol. Theresultant mixture was stirred and heated to 80° C. and held at thistemperature for one hour. The pellets dissolved, and a fine precipitateformed. The mixture was then cooled and chilled to 0° C. Theprecipitated solid was collected on a filter and washed with coldethanol. The filtrate was concentrated to yield a yellow/orange oil witha slight amine odor.

Results are illustrated in Table 1.

EXAMPLE 5

The procedure of Example 3 was followed substituting sodium hydroxidefor the potassium hydroxide.

Results are illustrated in Table 1.

COMPARATIVE EXAMPLE 5A

The procedure of Comparative Example 3 was followed substituting sodiumhydroxide for the potassium hydroxide.

Results are illustrated in Table 1.

EXAMPLE 6

The procedure of Example 4 was followed substituting sodium hydroxidefor the potassium hydroxide.

Results are illustrated in Table 1.

                  TABLE 1                                                         ______________________________________                                        Preparation of Didecyldimethylammonium Hydroxide from                         Stoichiometric Amounts of Reactants                                           Ex-                                                                           ample 3       3A      4      5     5A     6                                   ______________________________________                                        Hy-   KOH     KOH     KOH    NaOH  NaOH   NaOH                                droxide                                                                       Sol-  Etha-   Isopro- n-propa-                                                                             Etha- Isopropyl                                                                            n-propa-                            vent  nol     panol   nol    nol          nol                                 Con-  96      86      95     81    66     83                                  version                                                                       ______________________________________                                    

Examples 3-6 when compared with Comparative Examples 3A and 5Ademonstrate that the use of a normal C₁ -C₄ alcohol as a reaction mediumenhances conversion of the chloride quat to the hydroxy quat.Furthermore, a comparison of examples 3 and 4 with Examples 5 and 6illustrates the increase in conversion by the use of the preferred metalhydroxide, potassium hydroxide.

EXAMPLE 7

The procedure of Example 3 was followed, but the mixture was heated to25° C. and held for one hour. Results are illustrated in Table 2.

EXAMPLE 8

The procedure of Example 3 was followed, but the mixture was heated to60° C. and held for 0.6 hour.

Results are illustrated in Table 2.

EXAMPLE 9

The procedure of Example 3 was followed, but the mixture was heated to90° C. and held for 0.3 hour.

Results are illustrated in Table 2.

EXAMPLE 10

The procedure of Example 5 was followed, but the mixture was heated to25° C. for 3.5 hours.

Results are illustrated in Table 2.

EXAMPLE 11

The procedure of Example 5 was followed, but the mixture was heated to60° C. for 1.5 hours.

Results are illustrated in Table 2.

EXAMPLE 12

The procedure of Example 5 was followed, but the mixture was heated to90° C. for 1 hour.

Results are illustrated in Table 2.

                  TABLE 2                                                         ______________________________________                                        Temperature and Time of Reaction                                                     7     8       9       10    11    12                                   ______________________________________                                        Hydroxide                                                                              KOH     KOH     KOH   NaOH  NaOH  NaOH                               Temperature                                                                            25      60      90    25    60    90                                 (°C.)                                                                  Time (Hours)                                                                            1      0.6     0.3   3.5   1.5    1                                 Conversion                                                                             91      92      93    79    81    85                                 (%)                                                                           ______________________________________                                    

Examples 7-12 illustrate the effects of reaction temperatures and timeon conversion of chloride quat to hydroxy quat.

EXAMPLE 13

The procedure of Example 1 is followed substituting 0.4 moles of 80%octyldecyldimethylammonium chloride for the didecyldimethylammoniumchloride to yield octyldecyldimethylammonium hydroxide.

EXAMPLE 14

The procedure of Example 1 is followed substituting 0.4 moles of 80%iso-nonyldecyldimethylammonium chloride for the didecyldimethylammoniumchloride to yield iso-nonyldecyldimethylammonium hydroxide.

EXAMPLE 15

The procedure of Example 1 is followed substituting 0.4 moles of 80%benzyldodecyldimethylammonium chloride for the didecyldimethylammoniumchloride to yield benzyldodecyldimethylammonium hydroxide.

EXAMPLE 16

The procedure of Example 1 is followed substituting 0.4 moles of an 80%mixture of benzyldodecyl-; benzyltetradecyl-; andbenzylhexadecyldimethylammonium chloride for the didecyldimethylammoniumchloride to yield a mixture of benzyldodecyl-; benzyltetradecyl-; andbenzylhexadecyldimethylammonium hydroxide.

EXAMPLE 17

The procedure of Example 1 is followed substituting 0.4 moles of 80%dihexadecyldimethylammonium chloride for the didecyldimethylammoniumchloride to yield dihexadecyldimethylammonium hydroxide.

EXAMPLE 18

The procedure of Example 1 is followed substituting 0.4 moles of 80%dodecyltrimethylammonium chloride for the didecyldimethylammoniumchloride to yield dodecyltrimethylammonium hydroxide.

STOICHIOMETRIC EXCESS OF METAL HYDROXIDE EXAMPLE 19

A nitrogen purged reactor equipped with a heating mantle and a magneticstir bar was charged with 0.4 mole of 80% didecyldimethylammoniumchloride (144 grams of DDAC) in 20% ethanol/water, 180 ml of ethanol,and 0.49 mole of 85% potassium hydroxide (27.5 grams of KOH) pellets.The mixture was heated at 60°-70° C. for 3 hours, allowed to cool toroom temperature, and then cooled to 0° C. for about one hour toprecipitate potassium chloride. The precipitate was collected on avacuum filter, and the solid was washed with cold ethanol. Potassiumchloride yield was 30.8 grams.

The supernatant solution, which contained the hydroxy quat and 0.09moles of excess potassium hydroxide, was stirred with 2 grams (0,045moles) of carbon dioxide gas (from dry ice). The mixture was kept coldfor an hour and then was vacuum filtered to remove 7.2 grams(theoretical 6.2 grams) of potassium carbonate.

Conversion percentage to the hydroxy quat was determined to be 99%.

TREATMENT OF WOOD SUBSTRATES EXAMPLE 20

End grain pine wafers were weighed and then soaked withdidecyldimethylammonium hydroxide until a weight gain of 30% wasobserved.

The treated wafers were then placed in water and weighed periodically todetermine resistance to leaching.

Results are illustrated in FIGS. 1A and 1B.

COMPARATIVE EXAMPLE 20A

The procedure of Example 20 was followed substitutingdidecyldimethylammonium chloride for the didecyldimethylammoniumhydroxide.

Results are illustrated in FIGS. 1A and 1B.

FIGS. 1A and 1B illustrate that the hydroxy quat resists leaching forextended periods while the chloride quat leaches to levels of 1% or lessin a relatively short period.

EXAMPLE 21

A 10"×0.5"×0.75" piece of ponderosa pine was equilibrated, weighed, andheated for two hours at 60° C. The wood was treated with a treatingsolution of 2% didecyldimethylammonium hydroxide in water by heating inthe solution at 60° C. to 80° C. for one hour, cooling and standingovernight, and then being subjected to a second warm to cool cycle. Thesamples were allowed to dry to constant weight, and the uptake wasdetermined by comparing starting and finishing weights.

The samples were then heated for two hours at 60° C., and the weight ofthe warm treated samples was compared to the over dried sticks beforetreatment.

Results are illustrated in Table 3.

COMPARATIVE EXAMPLE 21A

The procedure of Example 21 was followed, omitting thedidecyldimethylammonium hydroxide from the treating solution.

COMPARATIVE EXAMPLE 21B

The procedure of Example 21 was followed, substitutingdidecyldimethylammonium chloride for the didecyldimethylammoniumhydroxide.

Results are illustrated in Table 3.

EXAMPLE 22

The procedure of Example 21 was followed substituting a solution of 1%didecyldimethylammonium hydroxide in 3% ammonia water for the solutionof the 2% didecyldimethylammonium hydroxide in water.

Results are illustrated in Table 3.

COMPARATIVE EXAMPLE 22A

The procedure of Example 22 was followed, omitting thedidecydimethylammonium hydroxide from the treating solution.

Results are illustrated in Table 3.

COMPARATIVE EXAMPLE 22B

The procedure of Example 22 was followed, substitutingdidecyldimethylammonium chloride for the didecyldimethylammoniumhydroxide.

Results are illustrated in Table 3.

                  TABLE 3                                                         ______________________________________                                        Weight Uptake from Quat Solutions                                             Example                                                                              21      21A     21B    22    22A   22B                                 ______________________________________                                        Solvent                                                                              Water   Water   Water  3%    3%    3%                                                                Ammo- Ammo- Ammonia                                                           nia   nia                                       Quat   Hy-     --      Chloride                                                                             Hy-   --    Chloride                                   droxide                droxide                                         Weight 2.5     -0.4    0.6    1.6   -0.6  2.0                                 Uptake                                                                        (%)                                                                           ______________________________________                                    

Examples 21 and 22, when compared with Comparative Examples 21A, 21B,22A, and 22B respectively, illustrate the ability of the hydroxy quatsprepared according to the present invention to be applied to woodsubstrates. The hydroxy quat is absorbed better than the chloride quatin water, and is absorbed similarly to the art accepted chloride quat inammonia/water. However, the hydroxy quats can be used without metalcoupling agents in treating wood substrates.

EXAMPLE 23

A piece of wood was treated according to the procedure of Example 21.The piece of wood was then soaked in water at room temperature for 24hours, dried to constant weight, and weighed to determine how muchchemical remained. The piece of wood was soaked for 96 additional hours(120 hours total), dried to constant weight, and weighed to determinethe leaching of quat from the treated wood. The water was changedseveral times during this period.

Results are illustrated in Table 4.

COMPARATIVE EXAMPLE 23A

A piece of wood was treated according to the procedure of ComparativeExample 21A.. The piece of wood was then soaked according to theprocedure of Example 23.

Results are illustrated in Table 4.

COMPARATIVE EXAMPLE 23B

A piece of wood was treated according to the procedure of ComparativeExample 21B. The piece of wood was then soaked according to theprocedure of Example 23.

Results are illustrated in Table 4.

EXAMPLE 24

A piece of wood was treated according to the procedure of Example 22.The piece of wood was then soaked according to the procedure of Example23.

Results are illustrated in Table 4.

COMPARATIVE EXAMPLE 24A

A piece of wood was treated according to the procedure of ComparativeExample 22A. The piece of wood was then soaked according to theprocedure of Example 23.

Results are illustrated in Table 4.

COMPARATIVE EXAMPLE 24B

A piece of wood was treated according to the procedure of ComparativeExample 22B. The piece of wood was then soaked according to theprocedure of Example 23.

Results are illustrated in Table 4.

                  TABLE 4                                                         ______________________________________                                        Leaching of Quat                                                              Example                                                                              23      23A     23B    24    24A   24B                                 ______________________________________                                        Solvent                                                                              Water   Water   Water  3%    3%    3%                                                                Ammo- Ammo- Ammonia                                                           nia   nia                                       Quat   Hy-             Chloride                                                                             Hy-         Chloride                                   droxide                droxide                                         Weight 2.5     0.4     0.6    1.6   0.6   2.0                                 Uptake                                                                        (%)                                                                           Retained                                                                             2.3/92  -0.2/-- 0.5/83 1.8/110                                                                             -0.3/--                                                                             1.7/85                              Quat at                                                                       24 Hours                                                                      (Abso-                                                                        lute %/                                                                       Relative                                                                      %)                                                                            Retained                                                                             1.8/72  -0.2/-- 0.4/67 1.3/81                                                                              -0.3/--                                                                             1.3/65                              Quat at                                                                       120                                                                           Hours                                                                         (Abso-                                                                        lute %/                                                                       Relative                                                                      %)                                                                            ______________________________________                                    

Example 23, when compared with Comparative Examples 23A and 23B, andExample 24, when compared with Comparative Examples 24A and 24B,demonstrate the improved retention properties of hydroxy quats preparedaccording to the present invention over conventional chloride quats,particularly in the absence of metal stabilizers.

All patents, applications, articles, publications, and test methodsmentioned above are hereby incorporated by reference.

Many variations of the present invention will suggest themselves tothose skilled in the art in light of the above detailed description.Such obvious variations are within the full intended scope of theappended claims.

I claim:
 1. A method for the preparation of C₁ -C₂₀ alkyl oraryl-substituted alkyl, C₈ -C₂₀ alkyl quaternary ammonium hydroxide,said method comprising(a) reacting a C₁ -C₂₀ alkyl or aryl-substitutedalkyl, C₈ -C₂₀ alkyl quaternary ammonium chloride reactant and a metalhydroxide reactant in a solvent comprising a C₁ -C₄ normal alcohol, saidmetal hydroxide being present in an amount sufficient to yield said C₁-C₂₀ alkyl or aryl-substituted alkyl, C₈ -C₂₀ alkyl quaternary ammoniumhydroxide; and (b) removing any excess metal hydroxide by reacting withcarbon dioxide.
 2. A method as defined in claim 1 wherein said C₁ -C₂₀alkyl or aryl-substituted alkyl is selected from the group consisting ofa methyl, C₈ alkyl, C₉ isoalkyl, C₁₀ alkyl, C₁₂ alkyl, C₁₄ alkyl, C₁₆alkyl, and benzyl group, and said C₈ -C₂₀ alkyl group is selected fromthe group consisting of a C₁₀ alkyl, C₁₂ alkyl, C₁₄ alkyl, and C₁₆ alkylgroup.
 3. A method for the preparation of di C₈ -C₁₂ alkyl quaternaryammonium hydroxide, said method comprising(a) reacting a di C₈ -C₁₂alkyl quaternary ammonium chloride reactant and a metal hydroxidereactant in a solvent comprising a C₁ -C₄ normal alcohol, said metalhydroxide being present in an amount sufficient to yield said di C₈ -C₁₂alkyl quaternary ammonium hydroxide.
 4. A method as defined in claim 3wherein said di C₈ -C₁₂ alkyl quaternary ammonium hydroxide comprisesdidecyldimethylammonium hydroxide and wherein said di C₈ -C₁₂ alkylquaternary ammonium chloride comprises didecyldimethylammonium chloride.5. A method as defined in claim 3 wherein said metal hydroxide comprisespotassium hydroxide.
 6. A method as defined in claim 3 wherein said C₁-C₄ normal alcohol comprises ethanol.
 7. A method as defined in claim 3wherein said di C₈ -C₁₂ alkyl quaternary ammonium hydroxide comprisesdidecyldimethylammonium hydroxide, said di C₈ -C₁₂ quaternary ammoniumchloride comprises didecyldimethylammonium chloride, and said C₁ -C₄normal alcohol comprises ethanol.
 8. A method as defined in claim 5wherein said amount of potassium hydroxide is a stoichiometric amountwith respect to said didecyldimethylammonium chloride.
 9. A method asdefined in claim 5 wherein said amount of potassium hydroxide is astoichiometric excess with respect to said didecyldimethylammoniumchloride.
 10. A method as defined in claim 9 wherein said excess rangesfrom about 2% to about 20% over a stoichiometric amount.
 11. A methodfor the preparation of didecyldimethylammonium hydroxide, said methodcomprising(a) reacting didecyldimethylammonium chloride and potassiumhydroxide in ethanol, said potassium hydroxide being present in at leasta stoichiometric amount with respect to said didecyldimethylammoniumchloride; and (b) removing any excess metal hydroxide by reacting withcarbon dioxide.
 12. A method as defined in claim 1 wherein said C₁ -C₄normal alcohol is selected from the group consisting of ethanol,n-propanol, and a combination thereof.
 13. A method for the preparationof C₁ -C₂₀ alkyl or aryl-substituted alkyl, C₈ -C₂₀ alkyl quaternaryammonium hydroxide, said method comprising(a) reacting a C₁ -C₂₀ alkylor aryl-substituted alkyl, C₈ -C₂₀ alkyl quaternary ammonium chloridereactant and a metal hydroxide reactant in a solvent comprising a C₁ -C₄normal alcohol, said metal hydroxide being present in an amountsufficient to yield said C₁ -C₂₀ alkyl or aryl-substituted alkyl, C₈-C₂₀ alkyl quaternary ammonium hydroxide wherein the weight ratio ofquaternary ammonium chloride to solvent is about 1.1:1; and (b) removingany excess metal hydroxide by reacting with carbon dioxide.
 14. A methodfor the preparation of C₁ -C₂₀ alkyl or aryl-substituted alkyl, C₈ -C₂₀alkyl quaternary ammonium hydroxide, said method comprising(a) reactinga C₁ -C₂₀ alkyl or aryl-substituted alkyl, C₈ -C₂₀ alkyl quaternaryammonium chloride reactant and a stoichiometric amount of potassiumhydroxide in a solvent comprising a C₁ -C₄ normal alcohol, to yield saidC₁ -C₂₀ alkyl or aryl-substituted alkyl, C₈ -C₂₀ alkyl quaternaryammonium hydroxide; and (b) removing any excess potassium hydroxide byreacting with carbon dioxide.
 15. A method for the preparation of C₁-C₂₀ alkyl or aryl-substituted alkyl, C₈ 614 C₂₀ alkyl quaternaryammonium hydroxide, said method comprising(a) reacting a C₁ -C₂₀ alkylor aryl-substituted alkyl, C₈ -C₂₀ alkyl quaternary ammonium chloridereactant and potassium hydroxide reactant in a solvent comprising anaqueous C₁ -C₄ normal alcohol, said potassium hydroxide being present inan amount sufficient to yield said C₁ -C₂₀ alkyl or aryl-substitutedalkyl, C₈ -C₂₀ alkyl quaternary ammonium hydroxide; and (b) removing anyexcess potassium hydroxide by reacting with carbon dioxide.